Part number decal would be found in the battery compartment (if still there). Hobbymasters website also has free parts diagrams. You would have to look through them to find your exact model. They are listed by model number and a brief description. Posting a pic is an option. The dune beetle was the larger two-seater 12v model and they made several small 6v one-seaters. I don't think the larger bug decals are available. Also check the "for sale" section here. There was a member selling a large amount of decal sheets a few months ago. He may have what you need. Worth a look.